I. Field of the Invention
The present invention relates to valves and more particularly to an improved gate valve structure.
II. Description of the Related Art
U. S. Pat. No. 4, 741, 509 issued May 3, 1988 to Bunch et al for "Gate Valve With Improved Secondary Body to Bushing Seals" and U. S. Pat. No. 4, 878, 651 issued Nov. 7, 1989 to Meyer, Jr. for "Valve Seat Assembly" both disclose gate valve apparatus. The Bunch et al patent is directed to a bushing improvement and the Meyer, Jr. patent is directed to a retainer ring structure. Neither of these patents discloses or suggests the improved metal-to-metal seal surfaces of the present invention.